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71.
The applicability of sap flux (Fd) measurements to bamboo forests has not been studied. This study was undertaken to establish an optimal and effective design for stand-scale transpiration (E) estimates in a Moso bamboo forest. To this aim, we validated Fd measurements in Moso bamboos in a cut bamboo experiment. In addition, we analyzed how sample sizes affect the reliability of E estimates calculated from Fd and conducting culm area (AS_b). In the cut bamboo experiments, we found that Fd measurement using a 10 mm probe was a valid means of determining the water-use behavior of a Moso bamboo, although a specific correction was needed. Furthermore, we calculated E from stand AS_b (AS_stand) and mean stand Fd (JS). Employing Monte Carlo analysis, we examined potential errors associated with sample size in E, AS_stand, and JS using an original dataset with AS_b and Fd measured for 40 and 16 individuals, respectively. Consequently, we determined the optimal sample size for both AS_stand and JS estimates as 11. The optimal sample sizes for JS were almost the same under different vapor pressure deficit and soil moisture conditions. The optimal sample size for JS at the study site was less than that of a coniferous plantation in the same region probably owing to small individual-to-individual variations in sap flux in the Moso bamboo forest. Our study concludes that sap flux measurements are an applicable technique for assessing water use in Moso bamboo forests.  相似文献   
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A new valved conduit was developed using a canine aortic valve. The bioprosthetic valve was fixed with glutaraldehyde and epoxy compound (Denacol-EX313/810). A vascular graft composed of ultra-fine polyester fiber (10 mm in diameter, 200 mm in length) was used. Four dogs underwent apico-aortic valved conduit (AAVC) implantation and aortic banding (bypass group, BG), while another 4 dogs underwent aortic banding without AAVC implantation (control group, CG). Cardiac catheterization and angiocardiography were performed for assessment of hemodynamics 2 weeks and 6 months after surgery. Left ventricular systolic pressure, left ventricular end-diastolic pressure and the left ventricular-aortic pressure gradient differed significantly (P<0.01) between the BG and CG dogs. Left ventricular angiocardiography showed patency of the valved conduit in all the BG dogs. Echocardiography was performed before and 2, 4 and 6 months after surgery, and showed that while pressure overload caused concentric myocardial hypertrophy in the CG dogs, the left ventricle dilated eccentrically in the BG dogs. Furthermore, relief of left ventricular pressure overload by AAVC was maintained.  相似文献   
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近红外光谱分析技术在果蔬品质无损伤检测方面的应用   总被引:3,自引:0,他引:3  
介绍了近红外光谱分析技术的测量原理和分析程序,综述了其在无损检测水果内部品质方面的应用现状,指出应注意的问题,并展望其研究发展前景.  相似文献   
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Overwintering of the brown leaf spot fungus, Mycochaetophora gentianae, in infected gentian leaves was studied in Iwate, northern Japan. Sporophores were produced on overwintered, infected leaves when they were sampled from January to July, but not in August after incubation in high humidity at 15 °C. Symptoms developed on gentian plants grown in soil artificially infested with overwintered, infected leaves that were either left throughout the experiments or removed before planting. Few lesions developed when plants were grown in soil infested with conidia. These results indicate that M. gentianae can overwinter in infected leaves, which act as the primary inoculum source.  相似文献   
76.
We fabricated a prototype 3.25-MHz split-focus therapeutic transducer combined with a small 6.5-MHz imaging ultrasonic probe for transrectal treatment of prostate cancer and evaluated the feasibility of using split-focus high-intensity focused ultrasound (HIFU) to ablate localized tumor tissue without injuring the surrounding organs. We therefore established a localized tumor model by inoculating VX2 tumor into rabbit livers. The localized VX2 tumors of nine rabbits were transdermally treated with split-focus ablation at a peak intensity in water of 6 kW/cm2 for 4 s (6 shots) under the guidance of ultrasonic B-mode imaging. Necropsy a day after treatment found the surface of the livers and gastrointestinal tracts to be grossly normal. The VX2 tumors were completely coagulated and were surrounded by ablated liver tissue. The six shots of split-focus HIFU destroyed the VX2 tumors without injuring the liver surfaces or the surrounding organs. These results suggest that split-focus HIFU ablation could be an effective treatment of localized tumors.  相似文献   
77.
Serum samples from 191 ostriches (Struthio camelus) in Japan were tested for antibodies to Newcastle disease virus (NDV) and avian influenza virus (AIV). Twenty-two (12%) contained NDV-specific neutralizing antibodies by a virus-neutralization (VN) test without vaccination. Antibodies to AIV were not detected in the any sera by an agar gel precipitation test. Seven serum samples that had vaccinated with live NDV by eye drop were all positive by the VN test at 1 month post vaccination. A haemagglutination inhibition (HI) test for NDV seemed not to be suitable for ostriches because of non-specific agglutination of chicken red blood cells. No haemagglutinating viruses were isolated. This is the first report on detection of antibodies against NDV in ostriches in Japan.  相似文献   
78.
An insertion/deletion variant of a thymine base (T5 and T6) in exon 2 of porcine beta 3‐adrenergic receptor (ADRB3) gene has been described. In the current study, we made an association study between the ADRB3 polymorphisms and production traits in 735 Duroc pigs. The allele frequencies for the T5 and T6 alleles in our study population were 0.433 and 0.567, respectively. Any associations between ADRB3 genotype and average daily weight gain during test period, or backfat thickness and intramuscular fat content were not detected in either sex. However the size of the loin eye muscle area (EMA) was significantly associated with ADRB3 genotypes in gilts. T6‐homozygous gilts had a higher mean of EMA (40.6 ± 0.6 cm2) than T5‐homozygous (38.1 ± 0.4 cm2, P = 0.002) and heterozygous (38.8 ± 0.3 cm2, P = 0.034) gilts. This association was not detected in males. In addition, a multiple traits animal model best linear unbiased predictor (BLUP) analysis revealed that the T6‐homozygous genotype had positive effects on breeding value of EMA. Accordingly, we suggest that ADRB3 polymorphism has the potential to be an important genetic marker for prediction of EMA in Duroc pigs.  相似文献   
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